Pulling fuel injector leads..., Should the engine stumble? |
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Pulling fuel injector leads..., Should the engine stumble? |
BMartin914 |
Sep 29 2005, 02:56 PM
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#1
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||| Group: Members Posts: 1,408 Joined: 30-May 04 From: Oregon Member No.: 2,128 Region Association: Pacific Northwest |
Testing the functionality of my FI last night I decided to pull the injector leads one at a time to see if it made any dirfference in the running condition.
Pulled #1 and it kept running like nothing had happened. Pulled #4 and it died. Restarted it and pulled #2 and it kept running like it had been, pulled #3 and it died. Is this indicitive of something? I expected maybe a stumble, but not for it to die. |
phantom914 |
Sep 29 2005, 03:15 PM
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#2
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non-914-owner non-club member Group: Benefactors Posts: 1,013 Joined: 24-February 04 From: Covina,CA(North ofWest Covina) Member No.: 1,708 |
Definitely something wrong. The #1 and #2 injectors are not working or actually more likely, they are not being triggered. Are you counting the cylinders correctly? I thought that #1/#3 were paired and #2/#4 were paired.
Since a pair is bad, I suspect the trigger points or a wire harness problem. A bad ECU could cause it, but that is the least likely cause. To verify that it is not the injectors, swap the connections. Swap #1 and #2 and swap #3 with #4. Do your test again. If #1 and #2 now cause the engine to die and disconnecting #3 and #4 don't make a difference, then it is not the injectors. Andrew |
goose2 |
Sep 29 2005, 03:26 PM
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#3
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Senior Member Group: Members Posts: 976 Joined: 30-March 05 From: Eugene, Oregon Member No.: 3,847 Region Association: Pacific Northwest |
The injectors are diagonally paired on the trigger points but paired differently (laterally, I think) on the grounds. If you have 2 injectors not working and they are not diagonally opposed, check the grounds on top of the engine case.
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Katmanken |
Sep 29 2005, 03:47 PM
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#4
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You haven't seen me if anybody asks... Group: Members Posts: 4,738 Joined: 14-June 03 From: USA Member No.: 819 Region Association: Upper MidWest |
Make sure the injectors are plugged in correctly.
Since the 914 engine is batch fired, it fires in pairs. If one of the pairs is not working AND the injectors are plugged in wrong, your symptoms can happen. Ken |
Dave_Darling |
Sep 29 2005, 05:19 PM
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#5
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914 Idiot Group: Members Posts: 14,991 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
Check the injector grounds at the rear crank case seam. You may have to move some stuff to get to the ground lugs.
--DD |
BMartin914 |
Sep 30 2005, 09:23 AM
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#6
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||| Group: Members Posts: 1,408 Joined: 30-May 04 From: Oregon Member No.: 2,128 Region Association: Pacific Northwest |
All of my grounds have been tied into ONE by the PO. When I had it apart a couple of weeks ago, I cut off the old ground lead and soldered on a gold plated ring terminal and tied it into one of the case bolts on top of the engine.
As a result, all of my grounds should be good. I will ahve some time to look at it this evening and see if I can find anyhting else. |
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